3 mod rule for stock ecu?
11-26-20, 08:19 AM
#51
RX-7 Bad Ass
iTrader: (55)
I haven't read the thread and as I skimmed over I saw several knowledgable members have posted and I am sure my comment will contradict several of them. You can do any number of mods you want on stock twins and stock ecu as long as boost stays at 10psi or less. I have owned, raced, abused and sold well over 50 FDs with full 3" back exhaust(No catalytic coverter or restrictor plate what-so-ever), with stock ports and street ports on stock ecu over the last 18 years without a single issue as long as boost is kept at 10 psi or less. It is safe all day every day as long as boost as at 10 psi and you have a healthy fuel pump/system. You can add every bolt on under sun(IC, Twin power, intake etc) without worry as long as boost is limited to 10 psi. Simply remove the factory restrictor pills and bypass the precontrol and wastegate control solenoids and install quality manual boost controllers and enjoy. This goes for sequential or non-sequential setups.
Of course I've aged out of stinky loud exhausts
.Dale
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djseven (11-26-20)
11-26-20, 03:36 PM
#52
This is a good point you've made before. I think the big thing is many people can't wrap their head around boost control. It can be tricky to have good boost control with a 3" mid pipe - doable, but it can require putting some work in.
Of course I've aged out of stinky loud exhausts.
Dale
Of course I've aged out of stinky loud exhausts
.Dale
11-26-20, 06:30 PM
#53
Rotary Enthusiast
I would avoid the midpipe unless you are 100% sure you have no creep. You will BLOW YOUR MOTOR. I would save midpipe for bigger injectors and tune. Or if you must try mid pipe use a restriction plate or something.
11-26-20, 08:37 PM
#54
That was on an engine I built for him and that car ended up setting, as far as I know, and still holding the 1/4 mile record on stock twins going 10.8@129. By my standards it had fairly small/medium intake porting and stock exhaust ports. Going off memory I think he made 360-370rwhp on a stock port reman running sequential and the car went 11.1@125-127 before the motor I built and he went NS. Its been a long time but I think that information is all correct.
That's a pretty badass engine you built him.
11-30-20, 02:22 PM
#55
Full Member
Thread Starter
remove the factory restrictor pill and by pass or eco from and wastegate solenoids? Can you please elaborate or point me in this direction?
thank you
thank you
I haven't read the thread and as I skimmed over I saw several knowledgable members have posted and I am sure my comment will contradict several of them. You can do any number of mods you want on stock twins and stock ecu as long as boost stays at 10psi or less. I have owned, raced, abused and sold well over 50 FDs with full 3" back exhaust(No catalytic coverter or restrictor plate what-so-ever), with stock ports and street ports on stock ecu over the last 18 years without a single issue as long as boost is kept at 10 psi or less. It is safe all day every day as long as boost as at 10 psi and you have a healthy fuel pump/system. You can add every bolt on under sun(IC, Twin power, intake etc) without worry as long as boost is limited to 10 psi. Simply remove the factory restrictor pills and bypass the precontrol and wastegate control solenoids and install quality manual boost controllers and enjoy. This goes for sequential or non-sequential setups.
12-01-20, 07:53 AM
#56
Supra pump straight drop in can handle more power than the twins can make. Denso quality. 12psi watching afr. ....... could be ok with the base map in the pfc or have Ari mod it a bit from RX7.com. I am pretty sure 12psi should work if injector duty is under control. Watch to cool nights
I would avoid the midpipe unless you are 100% sure you have no creep. You will BLOW YOUR MOTOR. I would save midpipe for bigger injectors and tune. Or if you must try mid pipe use a restriction plate or something.
I would avoid the midpipe unless you are 100% sure you have no creep. You will BLOW YOUR MOTOR. I would save midpipe for bigger injectors and tune. Or if you must try mid pipe use a restriction plate or something.
I would hate to have a car where I have to "Watch cool nights". Also... How can they watch anything with a stock ECU?
12-01-20, 08:14 AM
#57
Rotary Enthusiast
[QUOTE=alexdimen;12446231]The fuel cut table I have shows that they will hit fuel cut on the stock ecu at 12psi in the top of the rev range.
I would hate to have a car where I have to "Watch cool nights". Also... How can they watch anything with a stock ECU?
You watch with a stock ecu, haltech, pfc, or any ecu..... with an afr gauge. I wouldn't want to be running boost at a level were I have to "watch cool nights" either. Unfortunate some people apparently set themselves up that way and if they do not have enough restriction they can creep.... creep can equal blown motor...
That is why I said I would 100% make sure you have no creep. If you must have a midpipe and you have no creep, "watch the cool nights". Watch your afr.
There was a big discussion a long time ago that 10psi does not = 10psi for afr. Like exhaust gas left in chamber for another cycle is not going to equal a fresh stroke. Etc, etc. OP can do whatever he wants. I would simply advise against a midpipe because in my own experience I had issues. I know a few people whom had issues.
Supra pump will help after pfc (or whatever) and you want to raise boost up to around 12. I should have clarifed that it may not or would not help on stock ecu.... does that sound better?
I would hate to have a car where I have to "Watch cool nights". Also... How can they watch anything with a stock ECU?
You watch with a stock ecu, haltech, pfc, or any ecu..... with an afr gauge. I wouldn't want to be running boost at a level were I have to "watch cool nights" either. Unfortunate some people apparently set themselves up that way and if they do not have enough restriction they can creep.... creep can equal blown motor...
That is why I said I would 100% make sure you have no creep. If you must have a midpipe and you have no creep, "watch the cool nights". Watch your afr.
There was a big discussion a long time ago that 10psi does not = 10psi for afr. Like exhaust gas left in chamber for another cycle is not going to equal a fresh stroke. Etc, etc. OP can do whatever he wants. I would simply advise against a midpipe because in my own experience I had issues. I know a few people whom had issues.
Supra pump will help after pfc (or whatever) and you want to raise boost up to around 12. I should have clarifed that it may not or would not help on stock ecu.... does that sound better?
Last edited by Testrun; 12-01-20 at 08:17 AM.
12-01-20, 08:29 AM
#58
Racecar - Formula 2000
The fuel cut table I have shows that they will hit fuel cut on the stock ecu at 12psi in the top of the rev range....
While dual Hallman MBC's do technically work as a replacement for the stock boost control solenoids, they suck for boost response and transition. You lose some pre-spool of the secondary and you lose the ability of the ECU to hold open the precontrol gate after transition, which creates an unwanted restriction on your secondary turbo. It is not ideal. Power FC allows you to retain computer control of the WG and PC solenoids and control boost. Win-win. I have used both methods to control the twins.
While dual Hallman MBC's do technically work as a replacement for the stock boost control solenoids, they suck for boost response and transition. You lose some pre-spool of the secondary and you lose the ability of the ECU to hold open the precontrol gate after transition, which creates an unwanted restriction on your secondary turbo. It is not ideal. Power FC allows you to retain computer control of the WG and PC solenoids and control boost. Win-win. I have used both methods to control the twins.
My setup:
https://www.rx7club.com/3rd-generati...ht=ball-spring
Last edited by DaveW; 12-01-20 at 01:26 PM.
12-01-20, 09:42 AM
#59
I'm not saying it doesn't work. I am saying it doesn't work as well as the stock system.
FD's with MBCs are still a blast to drive. I had one, but eventually I wanted to compete with and beat modern cars at autocross and the stock control turbo system is much better suited for that.
I've been back to back to back from stock ECU boost control (was hitting fuel cut), so I went to MBCs, and then to PFC with stock solenoids.
The "kick" at transition I would guess is from the secondary turbo not being spooled up properly by the PC duty cycling. With a MBC the precontrol is closed until the spring pressure is overcome and it is suddenly slammed with boost pressure. It's like an on-off switch. The stock system and PFC duty cycle the PC, which allows more exhaust flow through the secondary turbine to spin it up during primary boost. If the secondary is not pre-spooled you are opening the turbo control actuator door and slamming a slow turbine with exhaust flow.
With an MBC at the top end after transition there is going to be a restriction at the secondary turbo because you can't isolate and force the precontrol door wide open like the stock ECU or PFC does.
With MBC's how can you ever be sure if you're controlling boost with the PC, WG, or some combination of the two. There's many good reasons Mazda separated them and controlled them individually.
FD's with MBCs are still a blast to drive. I had one, but eventually I wanted to compete with and beat modern cars at autocross and the stock control turbo system is much better suited for that.
I've been back to back to back from stock ECU boost control (was hitting fuel cut), so I went to MBCs, and then to PFC with stock solenoids.
The "kick" at transition I would guess is from the secondary turbo not being spooled up properly by the PC duty cycling. With a MBC the precontrol is closed until the spring pressure is overcome and it is suddenly slammed with boost pressure. It's like an on-off switch. The stock system and PFC duty cycle the PC, which allows more exhaust flow through the secondary turbine to spin it up during primary boost. If the secondary is not pre-spooled you are opening the turbo control actuator door and slamming a slow turbine with exhaust flow.
With an MBC at the top end after transition there is going to be a restriction at the secondary turbo because you can't isolate and force the precontrol door wide open like the stock ECU or PFC does.
With MBC's how can you ever be sure if you're controlling boost with the PC, WG, or some combination of the two. There's many good reasons Mazda separated them and controlled them individually.
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SpinningDorito (12-01-20)
12-01-20, 09:59 AM
#60
Racecar - Formula 2000
I'm not saying it doesn't work. I am saying it doesn't work as well as the stock system.
FD's with MBCs are still a blast to drive. I had one, but eventually I wanted to compete with and beat modern cars at autocross and the stock control turbo system is much better suited for that.
I've been back to back to back from stock ECU boost control (was hitting fuel cut), so I went to MBCs, and then to PFC with stock solenoids.
The "kick" at transition I would guess is from the secondary turbo not being spooled up properly by the PC duty cycling. With a MBC the precontrol is closed until the spring pressure is overcome and it is suddenly slammed with boost pressure. It's like an on-off switch. The stock system and PFC duty cycle the PC, which allows more exhaust flow through the secondary turbine to spin it up during primary boost. If the secondary is not pre-spooled you are opening the turbo control actuator door and slamming a slow turbine with exhaust flow.
With an MBC at the top end after transition there is going to be a restriction at the secondary turbo because you can't isolate and force the precontrol door wide open like the stock ECU or PFC does.
With MBC's how can you ever be sure if you're controlling boost with the PC, WG, or some combination of the two. There's many good reasons Mazda separated them and controlled them individually.
FD's with MBCs are still a blast to drive. I had one, but eventually I wanted to compete with and beat modern cars at autocross and the stock control turbo system is much better suited for that.
I've been back to back to back from stock ECU boost control (was hitting fuel cut), so I went to MBCs, and then to PFC with stock solenoids.
The "kick" at transition I would guess is from the secondary turbo not being spooled up properly by the PC duty cycling. With a MBC the precontrol is closed until the spring pressure is overcome and it is suddenly slammed with boost pressure. It's like an on-off switch. The stock system and PFC duty cycle the PC, which allows more exhaust flow through the secondary turbine to spin it up during primary boost. If the secondary is not pre-spooled you are opening the turbo control actuator door and slamming a slow turbine with exhaust flow.
With an MBC at the top end after transition there is going to be a restriction at the secondary turbo because you can't isolate and force the precontrol door wide open like the stock ECU or PFC does.
With MBC's how can you ever be sure if you're controlling boost with the PC, WG, or some combination of the two. There's many good reasons Mazda separated them and controlled them individually.
Last edited by DaveW; 12-01-20 at 01:34 PM.
12-05-20, 08:10 PM
#61
Glad we’ve been having this discussion. Bone stock JDM 94 (so no pre-cat...you could consider that a “mod” compared to US.) Installed the Autoexe intake, got worried about over boost, and installed a gauge.
In 1st I saw 15psi before I backed of. In 3rd/4th I saw 12/10/12.
In 1st I saw 15psi before I backed of. In 3rd/4th I saw 12/10/12.
12-06-20, 11:42 AM
#62
I disagree that FD with MBC on precontrol and WG actuators doesnt work as well as stock.
When I had my FD on stock ECU, 10psi boost with just upraded smic (stock duct type), downpipe and catback I had the boost and transition dialed in with Hallman Pro RXs so it was seamless (and it stayed dialed in- didnt wander with weather, elevation, time, etc).
I had raced the previous season in stock class (just catback) and hated the stock sequential transition with the dip and spike.
Now with ROM tuned ECU, 14psi downpipe, midpipe, catback, huge SMIC and M2 airbox the transition IS a bit wonky on the MBCs. Primary hits hard, runs out of flow so boost drops before transition and then bam 2nd turbo comes on full boost. Cant fix it.
When I had my FD on stock ECU, 10psi boost with just upraded smic (stock duct type), downpipe and catback I had the boost and transition dialed in with Hallman Pro RXs so it was seamless (and it stayed dialed in- didnt wander with weather, elevation, time, etc).
I had raced the previous season in stock class (just catback) and hated the stock sequential transition with the dip and spike.
Now with ROM tuned ECU, 14psi downpipe, midpipe, catback, huge SMIC and M2 airbox the transition IS a bit wonky on the MBCs. Primary hits hard, runs out of flow so boost drops before transition and then bam 2nd turbo comes on full boost. Cant fix it.
12-07-20, 11:33 AM
#63
Just to clarify - I am not saying you won't be able to control boost with MBCs. I had MBCs and found that boost control amount was actually more consistent than the stock system. That would make sense because you are working against spring pre-tension in the MBC and it always cracks open at the same pressures. The stock system is bleeding pressure based on a set point and target, which will react differently depending on air density and it's effects.
What I am saying is there are secondary functions to the pre-control door that you lose direct control of when you have MBC's.
You can't be sure that all of these things are happening:
1. Only the pre-control door is opening prior to transition so your secondary is getting pre-spooled as much as possible
2. Your pre-control door is completely open post transition
3. Your boost level is at your target(s) across the rev range
4. Transition is just right (how did you even tune transition with MBCs? that is controlled by the TCA)
With MBC's you have too much to balance, which is why controlling the function of each actuator via ECU is the only way to go.
Example:
Dave's pre-transition boost level is 11 PSI. How is that being regulated? If ONLY the PC is regulating primary boost at 11 psi, then he is getting good pre-spool of his secondary turbo. BUT that isn't possible because that would mean the WG is opening at 10 PSI intake pressure so the WG is opening before the PC. You might have a shot at getting it to work if your PC is set lower than your WG. And then either your primary boost is lower or your secondary boost is flirting with fuel cut on the stock ECU.
What I am saying is there are secondary functions to the pre-control door that you lose direct control of when you have MBC's.
You can't be sure that all of these things are happening:
1. Only the pre-control door is opening prior to transition so your secondary is getting pre-spooled as much as possible
2. Your pre-control door is completely open post transition
3. Your boost level is at your target(s) across the rev range
4. Transition is just right (how did you even tune transition with MBCs? that is controlled by the TCA)
With MBC's you have too much to balance, which is why controlling the function of each actuator via ECU is the only way to go.
Example:
Dave's pre-transition boost level is 11 PSI. How is that being regulated? If ONLY the PC is regulating primary boost at 11 psi, then he is getting good pre-spool of his secondary turbo. BUT that isn't possible because that would mean the WG is opening at 10 PSI intake pressure so the WG is opening before the PC. You might have a shot at getting it to work if your PC is set lower than your WG. And then either your primary boost is lower or your secondary boost is flirting with fuel cut on the stock ECU.
Last edited by alexdimen; 12-07-20 at 11:38 AM.
12-07-20, 12:40 PM
#64
Glad we’ve been having this discussion. Bone stock JDM 94 (so no pre-cat...you could consider that a “mod” compared to US.) Installed the Autoexe intake, got worried about over boost, and installed a gauge.
In 1st I saw 15psi before I backed of. In 3rd/4th I saw 12/10/12.
In 1st I saw 15psi before I backed of. In 3rd/4th I saw 12/10/12.
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j9fd3s (12-08-20),
madhat1111 (12-07-20)
12-07-20, 03:41 PM
#65
Racecar - Formula 2000
...Example:
Dave's pre-transition boost level is 11 PSI. How is that being regulated? If ONLY the PC is regulating primary boost at 11 psi, then he is getting good pre-spool of his secondary turbo. BUT that isn't possible because that would mean the WG is opening at 10 PSI intake pressure so the WG is opening before the PC. You might have a shot at getting it to work if your PC is set lower than your WG. And then either your primary boost is lower or your secondary boost is flirting with fuel cut on the stock ECU.
Dave's pre-transition boost level is 11 PSI. How is that being regulated? If ONLY the PC is regulating primary boost at 11 psi, then he is getting good pre-spool of his secondary turbo. BUT that isn't possible because that would mean the WG is opening at 10 PSI intake pressure so the WG is opening before the PC. You might have a shot at getting it to work if your PC is set lower than your WG. And then either your primary boost is lower or your secondary boost is flirting with fuel cut on the stock ECU.
You obviously have done much more sophisticated studying on the subject, so I will not argue the point that there would be a setup that works better. All I have to say is that I think my setup works very nicely and I have no reason to want to do anything different.
Last edited by DaveW; 12-08-20 at 07:59 AM.
12-08-20, 07:27 AM
#66
Alex, I don't pretend to know everything about boost control with MBC's or other methods, but I can tell you for a fact that I do get 11 psi on my boost gauge before transition, and I get 10 psi after with very little drop in between. I set those levels so that I would get a little more torque on the primary, and also be limited to 10 after transition so that there would be no chance of triggering fuel cut.
You obviously have done much more sophisticated studying on the subject, so I will not argue the point that there would be a setup that works better. All I have to say is that I think my setup works very nicely and I have no reason to do want to do anything different.
You obviously have done much more sophisticated studying on the subject, so I will not argue the point that there would be a setup that works better. All I have to say is that I think my setup works very nicely and I have no reason to do want to do anything different.
I also want to gain a better understanding of how these things work so I put this kind of stuff out there to be challenged and to challenge others.
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DaveW (12-08-20)
12-08-20, 09:00 AM
#67
RX-7 Bad Ass
iTrader: (55)
This is becoming a boost control thread .
Don't forget electronic boost controllers. I have an AVC-R and have had it for ages, works perfectly with smooth power all the way up.
Unless you have a way to control the factory boost solenoids (PFC) you need to remove them from the equation. Trying to play with pill size or use an MBC with them is super difficult.
The AVC-R is an unsung hero - it's complicated since it has so much functionality but that joker works. Boost by RPM, boost by gear, self-learning capability, even has an input to lower or raise boost - I have mine tied to my water injection, if the water tank is dry is basically turns boost control off. Also you can pick between 2 maps or disable the boost controller.
Dale
.Don't forget electronic boost controllers. I have an AVC-R and have had it for ages, works perfectly with smooth power all the way up.
Unless you have a way to control the factory boost solenoids (PFC) you need to remove them from the equation. Trying to play with pill size or use an MBC with them is super difficult.
The AVC-R is an unsung hero - it's complicated since it has so much functionality but that joker works. Boost by RPM, boost by gear, self-learning capability, even has an input to lower or raise boost - I have mine tied to my water injection, if the water tank is dry is basically turns boost control off. Also you can pick between 2 maps or disable the boost controller.
Dale
12-08-20, 09:40 AM
#68
This is becoming a boost control thread .
Don't forget electronic boost controllers. I have an AVC-R and have had it for ages, works perfectly with smooth power all the way up.
Unless you have a way to control the factory boost solenoids (PFC) you need to remove them from the equation. Trying to play with pill size or use an MBC with them is super difficult.
The AVC-R is an unsung hero - it's complicated since it has so much functionality but that joker works. Boost by RPM, boost by gear, self-learning capability, even has an input to lower or raise boost - I have mine tied to my water injection, if the water tank is dry is basically turns boost control off. Also you can pick between 2 maps or disable the boost controller.
Dale
.Don't forget electronic boost controllers. I have an AVC-R and have had it for ages, works perfectly with smooth power all the way up.
Unless you have a way to control the factory boost solenoids (PFC) you need to remove them from the equation. Trying to play with pill size or use an MBC with them is super difficult.
The AVC-R is an unsung hero - it's complicated since it has so much functionality but that joker works. Boost by RPM, boost by gear, self-learning capability, even has an input to lower or raise boost - I have mine tied to my water injection, if the water tank is dry is basically turns boost control off. Also you can pick between 2 maps or disable the boost controller.
Dale
I've drilled out my pills on my current build and will be running a pair of quality manual controllers. I've got a little more head room as being an S8 my boost on the OEM ECU is 10.8 PSI so I'll be setting my primary boost to 10.5 and secondary to 11 to ensure my pre-control gate is open fully during secondary operation... Or I may alter the springs and run 11 on both.
Interesting thread! I love how these cars are 30 years old and still confusing people, got to love the set up with the twins
.
Last edited by Ceylon; 12-08-20 at 09:45 AM.
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alexdimen (12-10-20)
12-08-20, 12:48 PM
#69
RX-7 Bad Ass
iTrader: (55)
I have my AVC-R set up with the waste gate and precontrol both T'd into the AVC-R actuator. Lots of people get worked up about this, "it's not gonna work!" "your turbo won't spool right!" - nope, it works perfectly.
I did that and also lowered the switchover point in the PFC. I have 2 settings, .8 (12psi) and 1.0 (14.7psi). Both are rock solid, hit hard with boost on the low end, and I have ZERO transition, just steady boost all the way up. I do have 99 280hp turbos with a ported waste gate.
People that have driven my car have commented on how much low end grunt it has. The combo really works well. There's no "RPM's drop down, have to spool back up" or anything weird, just floor it and get the boost you want, any time you want.
Dale
I did that and also lowered the switchover point in the PFC. I have 2 settings, .8 (12psi) and 1.0 (14.7psi). Both are rock solid, hit hard with boost on the low end, and I have ZERO transition, just steady boost all the way up. I do have 99 280hp turbos with a ported waste gate.
People that have driven my car have commented on how much low end grunt it has. The combo really works well. There's no "RPM's drop down, have to spool back up" or anything weird, just floor it and get the boost you want, any time you want.
Dale
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Mod Bugs (12-18-20)
12-08-20, 08:09 PM
#70
With the Hallman pro-rx on wastegate and pre-control you leave the stock ECU controlling TCA.
The perfectly smooth transition is achieved by 1st leaving precontrol MBC low and using the WG MBC to adjust post transition boost levels (you cant do this properly if you have boost creep). This eliminates variable of precontrol exhaust bleed affecting boost levels as when on primary turbo operation.
Then you tighten the Pre-control MBC till torque is stable on the transition to 2ndary turbo (boost gauge will flicker down- but no drop in torque because engine VE just jumped up).
Once you get Pre-control MBC dialed primary boost matches 2ndary because Mazda sized things to work this way.
It takes a bit of back and forth, but ends up working beautifully in my experience.
I bought my FD with dual MBC and went back to stock turbo control and pre-cat for Stock class racing. Hated the kick of torque when 2nd turbo came on with Stock class car (cat back exhaust). Went back to ASP with MBCs and downpipe and was able to dial in the transition perfect again in a couple hours. Was surprised it stayed perfect for 4 years till I modded up to 14psi.
The perfectly smooth transition is achieved by 1st leaving precontrol MBC low and using the WG MBC to adjust post transition boost levels (you cant do this properly if you have boost creep). This eliminates variable of precontrol exhaust bleed affecting boost levels as when on primary turbo operation.
Then you tighten the Pre-control MBC till torque is stable on the transition to 2ndary turbo (boost gauge will flicker down- but no drop in torque because engine VE just jumped up).
Once you get Pre-control MBC dialed primary boost matches 2ndary because Mazda sized things to work this way.
It takes a bit of back and forth, but ends up working beautifully in my experience.
I bought my FD with dual MBC and went back to stock turbo control and pre-cat for Stock class racing. Hated the kick of torque when 2nd turbo came on with Stock class car (cat back exhaust). Went back to ASP with MBCs and downpipe and was able to dial in the transition perfect again in a couple hours. Was surprised it stayed perfect for 4 years till I modded up to 14psi.
12-11-20, 11:24 AM
#71
RX-7 Bad Ass
iTrader: (55)
I will say with the manual boost controllers the good ones do work great but you start getting in the pricing territory of a used EBC really fast. Especially since you would need 2. But you would also need a place to mount the EBC in the car cleanly.
Blue TII, that's awesome that it worked that well for you and Thanks for the how-to on the tuning, that's the step that gets missed a lot in these discussions!
Dale
Blue TII, that's awesome that it worked that well for you and Thanks for the how-to on the tuning, that's the step that gets missed a lot in these discussions!
Dale
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alexdimen (12-11-20)
01-19-21, 11:39 AM
#72
You don't want to go catless on stock ECU, or any ECU, without porting the wastegate or having a restrictive exhaust. I question the benefit of adding a catless restriction when the stock main cat (not the US spec pre cat) is fine for a mildly modded car. I had good luck with catback and downpipe and stock airbox on my last FD, with stock ECU. It ran really well and I didn't have to worry about boost control issues.
If you keep the stock airbox and go with a high flow cat you should be ok. When you change the intake you increase boost and that can be a problem.
If you keep the stock airbox and go with a high flow cat you should be ok. When you change the intake you increase boost and that can be a problem.
01-20-21, 10:12 AM
#73
RX-7 Bad Ass
iTrader: (55)
Make sure you have a boost gauge. As stated, if you can keep boost to 10psi you will be good, either with boost control or a restrictor plate.
Dale
Dale
01-20-21, 02:24 PM
#75
For what it is worth, I didn't have any boost creep using the stock intake with the HKS downpipe, bonez high flo cat, and racing beats cat back, but I was using the PFC on a base map tune.
If you have a boost gauge I'd just take it out for a drive once you get everything installed and see what it tries to do.
If you have a boost gauge I'd just take it out for a drive once you get everything installed and see what it tries to do.